"(Trump's visit) will serve as an opportunity to address the North Korean nuclear issue based on the solid South Korea-US alliance and step up cooperation for peace and stability in Northeast Asia," Back Hye-ryun, the spokeswoman for the ruling Democratic Party, said in her commentary.

Back then called on the opposition parties to refrain from political attacks or accusations that she warned could undermine the summit talks.

The main opposition Liberty Korea Party also expressed its expectation that the Moon-Trump summit would help solidify the alliance particularly to better cope with the growing military tensions triggered by a provocative North Korea.

"Considering that Trump's visit comes when the allies have piles of significant issues such as the North's nuclear and missile problems and the Korea-US free trade agreement, we hope that the alliance will further be strengthened." Chung Woo-taik, the party's floor leader, said.

Chung also pledged to refrain from escalating its political offensive against the ruling bloc, stressing the importance of Moon's diplomacy with the US commander in chief.

The minor opposition People's Party, meanwhile, called on the Seoul government to thoroughly prepare to handle any possible pressure from Washington over trade, as Trump has complained of imbalances in two-way trade.

The Bareun Party demanded that the two leaders present a firm resolve against the North's persistent saber-rattling. (Yonhap)